Effect of Semi-sitting Position on Airway Clearance Obtained by Jaw Thrust During Oral Fiberoptic-Guided Intubation

Oral fiberoptic-guided intubation can be challenging in anesthetized patients due to loss of pharyngeal muscle tone, resulting in posterior displacement of the tongue, soft palate, and epiglottis. Maneuvers such as jaw thrust can improve patency, but their effectiveness may vary with patient position. Semi-sitting positioning has been shown to reduce upper airway collapsibility. This study compared airway clearance obtained by jaw thrust in the semi-sitting versus supine position during oral fiberoptic intubation.

This prospective randomized comparative study included adult American Society of Anesthesiologists (ASA) I-II patients aged 18-60 years undergoing elective surgery with orotracheal intubation. Patients were randomized into two groups: semi-sitting at 25° with jaw thrust (Group SS) and supine with jaw thrust (Group S). Airway clearance at the soft palate level (primary outcome) and at the epiglottis, time to visualize the vocal cords and carina, attempts required for tube advancement, total intubation time, and post-extubation airway trauma were assessed. Statistical analysis used chi-square and Student's t-test, with p<0.05 considered significant.

Sixty patients completed the study (30 per group). Airway clearance at the soft palate was significantly better in the semi-sitting group (p<0.001). Clearance at the epiglottis was comparable between groups (p=0.100). Time to visualize the vocal cords (12.35±6.68 vs. 15.99±5.37 s; p=0.024) and carina (19.92±7.10 vs. 25.05±7.03 s; p=0.007) was significantly shorter in the semi-sitting group. Tube advancement attempts, time for tube passage, total intubation time, and incidence of trauma or postoperative sore throat were similar across groups. No intubation failures or desaturation occurred.

Jaw thrust in the 25° semi-sitting position provides superior airway clearance at the soft palate and allows faster visualization of the vocal cords and carina during oral fiberoptic intubation. Overall intubation time and tube advancement characteristics remain similar between positions. Semi-sitting positioning may therefore be a useful adjunct to improve pharyngeal patency and facilitate fiberoptic-guided intubation in anesthetized patients.